There's really a lot of potential here, especially in terms of polish. I have a list of (hopefully constructive) critiques for you. Please don't take it too harshly, I'm only taking the time to write this because I think you are pretty talented, and that it might be valuable to you. I think you did a really good job with this, and I played it to the end and enjoyed it!
The attack ability: Firstly, I was confused, because on the itch page it says to "Left Click (Hold) - Charge attack" and "Right Click - Execute dash strike"... but I am pretty sure that's flipped. My confusion was furthered by the lack of cues that I was attacking. I almost quit trying to beat the game at level 3, until I realized that the charging indicator was the cursor getting smaller. This was completely unintuitive to me, and since there weren't any other cues that an attack was charging, I just thought it was broken. (and I also thought you had two seperate attacks from the description on the itch page, furthering my confusion). Since it is just a single charge ability, it may have been better to keep it on one button, and then activate it on release? This also means you can't cancel it, which could provide some interesting gameplay. But what it really is missing, is multiple cues: starting to swing the scythe behind you character, a sound when activating, and a sound that builds up until you release your attack.
The controls: It was a gamble, and I don't think it paid off. It felt like it was designed as a mobile game (it would make an excellent mobile game btw), and was frustrating to use when at the edges of the level, due to the slow-down - and in general a little frustrating because of the constant tracking you have to do. The design of the crosshair itself was pretty great though, so if I was making this game, I would definitely keep that as-is for the ability aim.
The visuals: are really great. I love your style. The vignette was a bit strong, to the point where the attack and health bar felt half-occluded. Digged the CRT distortion though, really fit the theme. One little detail was the hearts, I thought they were tongues for a solid 5 minutes.
The UI: looked great, but wasn't very functional. For one, for a game that exclusively uses the mouse, it is odd that the menu does not accept mouse input.
Audio: The choice of sounds itself is spot-on, it totally fits your style and theme - but some things really need sound. At first, I thought there might not even be sound in the game, until I was jumpscared by the murder sound. Even background music would get you a long way - but plenty of things lack cues to help with understanding.
The AI: could be a little unpredictable. I distinctly notices the AI do two different things in the same level, even though I did pretty much the same thing. Those damn things are hella complex though, and I think you've done a really good job with them in general. Just remember that good AI isn't necessarily smart AI, but predictable AI that the player can plan around.
The smallest little stuff: it was sort of odd to spawn in the middle of a corridor, with one direction being a dead-end. The projectile enemies didn't feel fun - this in general feeds into a bigger game design conundrum of how you play the game. Do you hope for the perfect run, setting it up just right? Or should there be counter-play when you are spotted? It feels like getting spotted in the hardest level is mostly a death sentence sometimes.
I hope you find some of this helpful, and not too harsh. You did a really good job with this!